Who was Bindeshwar Pathak, Sulabh founder who passed away?

Bindeshwar Pathak, founder of Sulabh International Social Service Organisation, passed away at a Delhi hospital. Born in Bihar's Vaishali, he graduated in sociology and led a nationwide sanitation movement spanning over five decades. In 1991, he was awarded Padma Bhushan for liberating manual scavengers and also for preventing environmental pollution by providing pour-flush toilet technology.